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#1 2021-May-19 16:11:41

sgv1975
Member
Registered: 2014-Oct-02
Posts: 20

Warp 3 stopped working

Hello,

In the middle of an experiment, my Warp V3 board started displaying 88 on the 7 segment displays. Additionally, all the lights around the two ethernet jacks are on, and the D5 LED is flickering.
Nothing obvious to me happened to cause this behavior.  I tried turning it off, and on again after a minute, and programming it with a couple of different designs (including the provided AP and STA references) through the Xilinx SDK and ChipscopePro. The SDK/Chipscope acted as if the device was successfully programmed, but after the programming completed, the board displayed the 88 number again and was non-functional.

I did see a similar prior message but there was no indication about whether programming the board worked. In a reply to that message, it was suggested to contact support[at]mangocomm.com to discuss repair options. I was wondering if this is still a possibility?


Thanks for your help.



SG

Last edited by sgv1975 (2021-May-19 18:53:42)

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#2 2021-May-19 20:28:05

murphpo
Administrator
From: Mango Communications
Registered: 2006-Jul-03
Posts: 5159

Re: Warp 3 stopped working

Based on the behavior you describe it might be a problem with one of the board's voltage regulators - I would guess it's the 12->3.7v regulator at U9, which would disable the reference clock but not FPGA config. You can confirm by measuring voltages at the red test points - refer to pg 14 in the schematics for the expected voltage at each. We (Mango) can no longer provide repair services. If you can isolate the failed component and want to attempt the repair, I would be happy to lookup the details in the BOM.

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#3 2021-May-19 22:23:35

sgv1975
Member
Registered: 2014-Oct-02
Posts: 20

Re: Warp 3 stopped working

Thanks for the quick reply. I probed the test points and verified that all of them except the 3.7V test point that is close to U9 have the correct voltage. The 3.7V test point is producing a sawtooth-like wave.  So, I believe that the U9 regulator has failed, as you suggested. I will try to replace this component as I really need the board to keep a project going.

It would be very helpful if you could let me know the complete component number for the regulator at U9 as the schematic has an x in the part number, and I did notice that similar TI parts come in a couple of different surface mount packages. 

Also, is there anything I should be mindful of when trying to replace the regulator? E.g. solder temperature so that I minimize the likelihood of moving other components when I use a hot air gun to de-solder it.

Additionally, when I tried to program the board again, after the program loaded, it started with an 88 on the 7 segment display, which changed to a 00 after a few seconds.

Thanks a lot for your help!

SG

Last edited by sgv1975 (2021-May-20 08:43:06)

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#4 2021-May-20 09:37:29

murphpo
Administrator
From: Mango Communications
Registered: 2006-Jul-03
Posts: 5159

Re: Warp 3 stopped working

U9: TI PTH08T260WAZ, also supports the PTH08T261WAZ, hence the 'x'. The 261 version doesn't require a electrolytic cap; the W3 has an electrolytic cap.

C7: Kemet T530Y687M004ATE005 - 680uF tantalum capacitor 2917 case

C61: Panasonic EEE-FP1E331AP - 330uF 10mm can aluminum electrolytic cap

The TI datasheet has some solder reflow temp limits. I would definitely recommend finding a technician with experience doing surface-mount, lead-free rework.

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#5 2021-May-20 10:02:53

sgv1975
Member
Registered: 2014-Oct-02
Posts: 20

Re: Warp 3 stopped working

Thank you so much for the parts and the advice on the technician.

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#6 2021-May-20 16:13:09

murphpo
Administrator
From: Mango Communications
Registered: 2006-Jul-03
Posts: 5159

Re: Warp 3 stopped working

Another thought - if the 3.7v regulator output is a saw wave, the problem might be with one of the output capacitors. First guess would be the tantalum cap at C7. It's worth replacing that and re-testing before replacing U9.

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#7 2021-Jun-04 09:50:49

sgv1975
Member
Registered: 2014-Oct-02
Posts: 20

Re: Warp 3 stopped working

Thanks for your help in debugging and finding the parts. Replacing the C7 cap was a good suggestion, but that was not sufficient in this case. I got a PCB rework company to replace all three parts and the board appears to work now. I am able to load a stock AP design and connect to it with a commodity 802.11 device.

Thanks!

Last edited by sgv1975 (2021-Jun-04 09:51:10)

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